Simultaneous biodegradation of phenolics and petroleum hydrocarbons from semi-coking wastewater: Construction of bacterial consortium and their metabolic division of labor

Phenols and petroleum hydrocarbons were the main contributors to COD in semi-coking wastewater, and their removal was urgent and worthwhile. The microbial strains were selected to construct microbial community for the wastewater treatment. The concentration of phenols was decreased from 2450 +/- 1.2 mg/L to 200 +/- 0.9 mg/L, and the removal rate of petroleum hydrocarbons was up to 97.08 +/- 0.09 % by microorganisms. After phenolic compounds with high toxicity were removed by bioaugmentation, the treated semi-coking wastewater was more biodegradable, and its water quality has been significantly improved. Through GC-MS and high-through sequencing technology, the metabolic division of labor in degradation of phenols, ring-cleavage of aromatic compounds, mineralization of metabolites was further revealed. The microbial community consisting of Pseudomonas stutzeri N2 and Rhodococcus qingshengii FF could effectively and simultaneously remove phenols and petroleum hydrocarbons, and these two strains possess great potential of being applied in aerobic biological treatment process of large-scale semi-coking wastewater.

Automated summary

Phenols and petroleum hydrocarbons were the main contributors to COD in semi-coking wastewater. Their removal from the wastewater was urgent and valuable. Microbial strains were selected to create a microbial community for the treatment of the wastewater. The concentration of phenols decreased from 2450 +/- 1.2 mg/L to 200 +/- 0.9 mg/L, and microorganisms achieved a petroleum hydrocarbon removal rate of up to 97.08 +/- 0.09%. After the bioaugmentation process removed highly toxic phenolic compounds, the treated semi-coking wastewater became more biodegradable and showed significant improvement in water quality. The metabolic division of labor in the degradation of phenols, ring-cleavage of aromatic compounds, and mineralization of metabolites was further revealed through GC-MS and high-throughput sequencing technology. The microbial community consisting of Pseudomonas stutzeri N2 and Rhodococcus qingshengii FF was able to effectively and simultaneously remove phenols and petroleum hydrocarbons, indicating their potential for application in the aerobic biological treatment of large-scale semi-coking wastewater.